'All American': What Happened With Spencer & Olivia Over Summer? Watch Tense Season 3 First Look (Exclusive)

ET exclusively debuts a clip from Monday's return.

What happened over the summer between Spencer and Olivia?

All American is back for season 3 on Monday and major changes are afoot. With Spencer James about to begin his senior year back at South Crenshaw High School and Billy taking over as coach of the football team, unresolved tensions with his old teammates at Beverly Hills High linger. As the fall semester kicks off, certain developments that took place during the summer add a layer of complication.

Spencer's arm may not have properly healed and Olivia's relapse with alcohol threatens to potentially ruin relationships and friendships. Meanwhile, there's also Jordan's impending fatherhood, Asher's possible reconciliation with his estranged mother and the return of Tyrone's sister, likely spelling doom for Coop.

In ET's exclusive sneak peek from the premiere, Spencer is back in the hallways of Beverly Hills High for one last hurrah with his former teammates and friends before he begins his senior year at South Crenshaw.

But while he and his old teammates plan to ring out summer vacation with a half-birthday party before they officially become rivals, there's noticeable tension between Spencer and Olivia when they lock eyes across the way. With Spencer and Olivia stuck in that big mansion together over the summer, what went down between them that may have caused a rift?

"Season 3 of All American focuses on the pressures of senior year for our favorite Beverly and Crenshaw teens," showrunner and executive producer Nkechi Okoro Carroll told ET in November. "They have been away from each other all summer and have now returned with some major summer secrets, the continuous fallout from which will truly test their friendships. And now that Spencer and Billy have rejoined Beverly rival, the South Crenshaw Chargers, the stakes of their football season aren't just high, they're personal."

All American premieres Monday, Jan. 18 at 8 p.m. ET/PT on The CW. For more on the series, watch below.

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